Systems and methods are described herein to implement transverse momentum injection at low frequencies to directly modify large-scale eddies in a turbulent boundary layer on a surface of an object. A set of transverse momentum injection actuators may be positioned on the surface of the object to affect large-scale eddies in the turbulent boundary layer. The system may include a controller to selectively actuate the transverse momentum injection actuators with an actuation pattern to affect the large-scale eddies to modify the drag of the fluid flow on the surface. In various embodiments, the transverse momentum injection actuators may be operated at frequencies less than 10,000 Hertz.

A drone-type air mobility vehicle includes a body, a plurality of rotors, and a plurality of rotor arms configured to connect the plurality of rotors to the body. The drone-type air mobility vehicle further includes: a plurality of air flaps provided in the rotor arms, respectively, and configured to be deployed downwards with the respect to the respective rotor arms by gas injected into the air flaps; and a controller configured to determine whether the rotors are abnormal, based on a yaw rate of the mobility vehicle and state information of the rotors, and the controller configured to determine whether to deploy the air flaps according to a result of the determination on whether the rotors are abnormal.

A drone-type air mobility vehicle includes a body, a plurality of rotors, and a plurality of rotor arms configured to connect the plurality of rotors to the body. The drone-type air mobility vehicle further includes: a plurality of air flaps provided in the rotor arms, respectively, and configured to be deployed downwards with the respect to the respective rotor arms by gas injected into the air flaps; and a controller configured to determine whether the rotors are abnormal, based on a yaw rate of the mobility vehicle and state information of the rotors, and the controller configured to determine whether to deploy the air flaps according to a result of the determination on whether the rotors are abnormal.

Truncated flap support fairings with active flow control system for aircraft and related methods are disclosed herein. An example aircraft includes a wing having a fixed wing portion, a flap moveably coupled to the fixed wing portion, a flap support fairing coupled to a bottom of the flap, the flap support fairing having an aft end, and an active flow control system including a nozzle. The nozzle is to eject high velocity air in a streamwise direction from the aft end of the flap support fairing.

Truncated flap support fairings with active flow control system for aircraft and related methods are disclosed herein. An example aircraft includes a wing having a fixed wing portion, a flap moveably coupled to the fixed wing portion, a flap support fairing coupled to a bottom of the flap, the flap support fairing having an aft end, and an active flow control system including a nozzle. The nozzle is to eject high velocity air in a streamwise direction from the aft end of the flap support fairing.

Flap actuation systems for aircraft are described herein. An example flap actuation system includes a fixed beam coupled to and extending downward from a fixed wing portion of an aircraft wing and a rocking lever plate pivotably coupled to the fixed beam. The rocking lever plate is coupled to a forward end of a flap bracket disposed on a bottom side of a flap of the wing. The flap actuation system also includes a crank arm, a crank rod coupled between the crank arm and the rocking lever plate, and a flap link coupled between the rocking lever plate and an aft end of the flap bracket, such that actuation of the crank arm pivots the rocking lever plate to move the flap between a stowed position and a deployed position relative to the fixed wing portion.

Flap actuation systems for aircraft are described herein. An example flap actuation system includes a fixed beam coupled to and extending downward from a fixed wing portion of an aircraft wing and a rocking lever plate pivotably coupled to the fixed beam. The rocking lever plate is coupled to a forward end of a flap bracket disposed on a bottom side of a flap of the wing. The flap actuation system also includes a crank arm, a crank rod coupled between the crank arm and the rocking lever plate, and a flap link coupled between the rocking lever plate and an aft end of the flap bracket, such that actuation of the crank arm pivots the rocking lever plate to move the flap between a stowed position and a deployed position relative to the fixed wing portion.

A flap actuation mechanism incorporates a coupler rod eccentrically supported at an aft end and at a forward end. The coupler rod is configured to translate from an aft position to a forward position. An inboard crank arm is coupled to the rotary actuator and engaged to the aft end of the coupler rod. The inboard crank is configured rotate responsive to rotation of the rotary actuator thereby inducing translation of the coupler rod. An outboard crank arm engaged to a forward end of the coupler rod and is configured to rotate responsive to translation of the coupler rod. A flap drive arm is attached to the outboard crank arm and is configured to rotate with the outboard crank arm from a stowed position to a deployed position responsive to translation of the coupler rod from the aft position to the forward position.

Systems and methods are described herein to implement transverse momentum injection at low frequencies to directly modify large-scale eddies in a turbulent boundary layer on a surface of an object. A set of transverse momentum injection actuators may be positioned on the surface of the object to affect large-scale eddies in the turbulent boundary layer. The system may include a controller to selectively actuate the transverse momentum injection actuators with an actuation pattern to affect the large-scale eddies to modify the drag of the fluid flow on the surface. In various embodiments, the transverse momentum injection actuators may be operated at frequencies less than 10,000 Hertz.

A simple, safe, and inexpensive flight control system in an aircraft. An anti-torque system for a rotary-wing aircraft has an airfoil with a first surface extending from a first trailing edge and a leading edge, and a second surface extending from a second trailing edge to join the first surface at the leading edge. The airfoil has a first moveable deflector panel pivotally coupled to the first trailing edge, and a second moveable deflector panel pivotally coupled to the second trailing edge. Means are provided to pivot the deflector panels in unison about their respective pivot axes to alter the direction of travel of the airflow downstream of the pivot axes over the surfaces of the deflector panels, thereby producing a lift in a direction perpendicular to the airflow to counteract the torque applied on the aircraft. The flight control system may be arranged within a fixed-wing aircraft.